Association of DNA repair gene XRCC1 and XPD polymorphisms with genetic susceptibility to gastric cancer in a Chinese population

Background: DNA repair gene polymorphisms can contribute to susceptibility of human cancer, including gastric cancer. Three single nucleotide polymorphisms (SNPs) of xeroderma pigmentosum group D (XPD) and X-ray repair cross complement 1 (XRCC1) genes were genotyped in gastric cancer and control subjects in a population from Southwestern China for their association with susceptibility of gastric cancer risk. Methods: 190 hospital-based cases and 180 matched controls were recruited and blood samples were collected from each of them and amplified with a PCR and DNA sequenced for XPD Asp312Asn, XRCC1 Arg194Trp, and XRCC1 Arg280Gln genotyping. Results: Allelic association analysis of these three SNPs showed that the frequency of XRCC1 194Trp in gastric cancer case and the control was 17.2% and 7.3%, respectively, which was significantly associated with gastric cancer risk (OR = 2.72, 95% CI: 1.04–7.24, p = 0.027). Furthermore, XRCC1 194Trp allele increased gastric carcinoma risk in male patients with older age and distant metastasis of gastric cancer. In addition, XRCC1 Trp allele but not XRCC1 Arg allele was closely associated to development of gastric cardia carcinoma. However, other SNPs did not show an association with gastric cancer risk or other clinicopathologic data of the patients. Conclusion: XRCC1 194Trp allele significantly increased the risk of gastric cancer and also associated with risk of gastric cardia carcinoma and promoted distant metastasis of gastric cancer. Future study will verify these findings for use of this SNP as biomarker in gastric cancer.